const CheerioShim = {
    load: (html) => {
        const parser = new DOMParser();
        const doc = parser.parseFromString(html, 'text/html');

        const $ = (selector, context) => {
            let elements;
            if (selector && selector.nodeType) {
                elements = [selector];
            } else if (Array.isArray(selector)) {
                elements = selector;
            } else {
                const root = (context && context[0]) ? context[0] : (context || doc);
                elements = Array.from(root.querySelectorAll ? root.querySelectorAll(selector) : []);
            }
            return createWrapper(elements);
        };

        function createWrapper(elements) {
            elements.forEach((el, i) => elements[i] = el);
            
            elements.attr = (name) => {
                if (elements.length === 0) return undefined;
                return elements[0].getAttribute ? elements[0].getAttribute(name) : null;
            };

            elements.text = () => {
                return elements.map(el => el.textContent).join('');
            };

            elements.find = (selector) => {
                let found = [];
                elements.forEach(el => {
                    if (el.querySelectorAll) {
                        found = found.concat(Array.from(el.querySelectorAll(selector)));
                    }
                });
                return createWrapper(found);
            };

            elements.each = (callback) => {
                elements.forEach((el, i) => {
                    callback(i, el);
                });
                return elements;
            };

            elements.map = (callback) => {
                const results = elements.map((el, i) => callback(i, el));
                return createWrapper(results.filter(r => r !== null && r !== undefined));
            };

            elements.get = () => Array.from(elements);

            elements.filter = (selectorOrFn) => {
                if (typeof selectorOrFn === 'function') {
                    return createWrapper(elements.filter(selectorOrFn));
                }
                return createWrapper(elements.filter(el => el.matches && el.matches(selectorOrFn)));
            };

            elements.first = () => createWrapper(elements.length ? [elements[0]] : []);
            elements.last = () => createWrapper(elements.length ? [elements[elements.length - 1]] : []);
            elements.eq = (i) => createWrapper(elements.length > i ? [elements[i]] : []);

            return elements;
        }

        return $;
    }
};

window.require = (moduleName) => {
    if (moduleName === 'cheerio') return CheerioShim;
    
    if (moduleName === 'node-fetch' || moduleName === 'fetch') return window.fetch.bind(window);
    
    return {}; 
};

window.module = { exports: {} };

class MockBrowser {
    constructor() {
    }

    async scrape(url, pageFn, options = {}) {
        emulatorLog(`[Browser] Scraping: ${url}`, 'info');
        
        try {
            const response = await fetch(url);
            if (!response.ok) throw new Error(`HTTP ${response.status}`);
            const html = await response.text();

            const parser = new DOMParser();
            const doc = parser.parseFromString(html, "text/html");

            return await this.executePageFn(pageFn, doc);

        } catch (error) {
            emulatorLog(`[Browser] Error: ${error.message}`, 'error');
            if (error.name === 'TypeError' && error.message.includes('Failed to fetch')) {
                emulatorLog('Tip: This looks like a CORS error. Ensure you have a "Allow CORS" extension enabled in your browser for testing.', 'warn');
            }
            throw error;
        }
    }

    async executePageFn(pageFn, virtualDoc) {
        const fnString = pageFn.toString();
        const wrapper = new Function("document", `return (${fnString})();`);
        return wrapper(virtualDoc);
    }
}

const codeInput = document.getElementById('code-input');
const runBtn = document.getElementById('run-btn');
const outputVisual = document.getElementById('visual-container');
const outputJson = document.getElementById('json-content');
const outputConsole = document.getElementById('console-content');

const originalConsoleLog = console.log;
const originalConsoleError = console.error;
const originalConsoleWarn = console.warn;

function captureLogs() {
    console.log = (...args) => {
        originalConsoleLog(...args);
        emulatorLog(args.map(a => typeof a === 'object' ? JSON.stringify(a) : String(a)).join(' '), 'info');
    };
    console.error = (...args) => {
        originalConsoleError(...args);
        emulatorLog(args.map(a => typeof a === 'object' ? JSON.stringify(a) : String(a)).join(' '), 'error');
    };
    console.warn = (...args) => {
        originalConsoleWarn(...args);
        emulatorLog(args.map(a => typeof a === 'object' ? JSON.stringify(a) : String(a)).join(' '), 'warn');
    };
}

function emulatorLog(msg, type = 'info') {
    const div = document.createElement('div');
    div.className = `log-entry log-${type}`;
    div.textContent = `[${new Date().toLocaleTimeString()}] ${msg}`;
    outputConsole.appendChild(div);
    outputConsole.scrollTop = outputConsole.scrollHeight;
}

window.switchTab = (tabName) => {
    ['visual', 'json', 'console'].forEach(t => {
        document.getElementById(`output-${t}`).classList.add('hidden');
    });
    document.getElementById(`output-${tabName}`).classList.remove('hidden');
    
    document.querySelectorAll('.tab-btn').forEach(btn => btn.classList.remove('active'));
    if (event && event.target) event.target.classList.add('active');
};

runBtn.addEventListener('click', async () => {
    outputVisual.innerHTML = '';
    outputJson.textContent = '';
    outputConsole.innerHTML = '';
    window.module.exports = {}; 
    captureLogs();  

    const code = codeInput.value;
    const functionName = document.getElementById('func-select').value;
    const argInput = document.getElementById('arg-input').value;
    const pageInput = parseInt(document.getElementById('page-input').value) || 1;

    if (!code.trim()) {
        alert("Please paste extension code first.");
        return;
    }

    emulatorLog("--- Starting Execution ---");

    try {
        try {
            new Function(code)();
        } catch (e) {
            throw new Error(`Syntax/Runtime Error in Extension Code: ${e.message}`);
        }

        const exports = window.module.exports;
        const keys = Object.keys(exports);
        if (keys.length === 0) throw new Error("No class found in module.exports. Did you add 'module.exports = { ClassName };'?");
        
        const ExtensionClass = exports[keys[0]];
        emulatorLog(`Loaded Class: ${keys[0]}`, 'info');

        const browserInstance = new MockBrowser();
        const extension = new ExtensionClass('node-fetch', 'cheerio', browserInstance);

        if (typeof extension[functionName] !== 'function') {
            throw new Error(`Function '${functionName}' not found in class '${keys[0]}'.`);
        }

        emulatorLog(`Calling ${functionName}('${argInput}', ${pageInput})...`);
        
        document.querySelector('.loading-state').classList.remove('hidden');
        
        let result;
        if (functionName === 'fetchSearchResult') {
            result = await extension.fetchSearchResult(argInput, pageInput);
        } else if (functionName === 'fetchInfo') {
            result = await extension.fetchInfo(argInput);
        } else if (functionName === 'findChapters') {
            result = await extension.findChapters(argInput);
        } else if (functionName === 'findChapterPages') {
            result = await extension.findChapterPages(argInput);
        }

        document.querySelector('.loading-state').classList.add('hidden');

        emulatorLog("Data received. Rendering...", 'info');
        renderJson(result);
        renderVisuals(result, functionName);
        
        if (result) switchTab('visual');

    } catch (err) {
        document.querySelector('.loading-state').classList.add('hidden');
        emulatorLog(err.message, 'error');
        console.error(err); 
    }
});

function renderJson(data) {
    outputJson.textContent = JSON.stringify(data, null, 2);
}

function renderVisuals(data, type) {
    outputVisual.innerHTML = '';

    if (!data) {
        outputVisual.innerHTML = '<div style="padding:1rem; color: #a1a1aa;">No data returned (null/undefined). Check Console for errors.</div>';
        return;
    }

    if (type === 'fetchSearchResult') {
        if (data.results && Array.isArray(data.results) && data.results.length > 0) {
            data.results.forEach(item => {
                const card = document.createElement('div');
                card.className = 'visual-card';
                
                const imgSrc = item.image || item.cover || item.sampleImageUrl || '';
                
                card.innerHTML = `
                    <img src="${imgSrc}" onerror="this.onerror=null;this.src='https://via.placeholder.com/150?text=Error';">
                    <div class="title" title="${item.title || item.id}">
                        ${item.title || ('ID: ' + item.id)}
                    </div>
                `;
                outputVisual.appendChild(card);
            });
        } else {
            outputVisual.innerHTML = '<div style="padding:1rem">No results found in "results" array.</div>';
        }
    }
    else if (type === 'findChapters') {
         if (data.chapters && Array.isArray(data.chapters)) {
            const list = document.createElement('div');
            list.style.cssText = 'display: flex; flex-direction: column; width: 100%; gap: 5px;';
            
            data.chapters.forEach(chap => {
                const row = document.createElement('div');
                row.className = 'visual-chapter';
                row.style.cssText = 'padding: 10px; background: var(--bg-surface); border-radius: 4px;';
                row.innerHTML = `<span style="color: var(--accent);">Ch. ${chap.chapter}</span> - ${chap.title} <br><small style="color:#666">${chap.id}</small>`;
                list.appendChild(row);
            });
            outputVisual.appendChild(list);
         } else {
             outputVisual.innerHTML = '<div>No chapters found. Check JSON.</div>';
         }
    }
    else if (type === 'findChapterPages') {
        if (Array.isArray(data)) {
            data.forEach(page => {
                if(page.type === 'text') {
                     const div = document.createElement('div');
                     div.innerHTML = page.content;
                     div.style.cssText = 'background: #fff; color: #000; padding: 20px; border-radius: 8px; margin-bottom: 20px;';
                     outputVisual.appendChild(div);
                } else {
                    const img = document.createElement('img');
                    img.src = page.url;
                    img.style.cssText = 'max-width: 100%; margin-bottom: 10px; border-radius: 4px;';
                    outputVisual.appendChild(img);
                }
            });
        } else {
            outputVisual.innerHTML = '<div>No pages array returned.</div>';
        }
    }
    else if (type === 'fetchInfo') {
        const container = document.createElement('div');
        container.style.padding = '1rem';
        if (data.fullImage) {
            container.innerHTML += `<img src="${data.fullImage}" style="max-height: 300px; display: block; margin-bottom: 1rem;">`;
        }
        container.innerHTML += `<pre>${JSON.stringify(data, null, 2)}</pre>`;
        outputVisual.appendChild(container);
    }
}